A conventional gas oven for burning liquid petroleam gas or natural gas such as for family cooking purpose may include a gas valve means as shown in FIGS. 1, 1A, 2 and 2A.
The gas valve means includes a valve body 10 having a gas inlet port 12 vertically formed in a gas tube adapter 13 for directing fuel gas into the port 12 (direction G), a rotor plug hole 11 horizontally formed in the valve body 10 perpendicularly communicating the gas inlet port 12 for rotatably engaging a rotor plug 20 in the hole 11, and a rotating knob 30 secured with the rotor plug 20 rotatably mounted on the gas oven (not shown) for operating the rotor plug 20 for adjusting gas flow rate to a burning nozzle of the oven. The plug 20 normally seals the gas inlet port 12 for closing the gas valve.
The rotor plug 20 is formed with a central longitudinal hole 21 about a longitudinal axis 210 of the plug 20, a large gas inlet opening 211 radially formed through a cross section of the plug 20 perpendicularly intersecting and communicating the central longitudinal hole 21 having a large gas outlet opening 213 formed in an opposite end of the inlet opening 211 on a perimeter of the plug 20 communicating with a first gas passage 113 formed in the valve body 10 to be finally connected with an outer large gas nozzle 115 of a gas burner, a small gas inlet opening 212 radially formed in the plug 20 to be angularly separated from the large opening 211 along a cross sectional plane perpendicular to the longitudinal axis 210 and communicating with the central longitudinal hole 21 and communicating a second gas passage 112 formed in the valve body 10 to be finally connected with an inner small gas nozzle 114 of the gas burner 114, a pilot gas outlet opening 214 formed in an outer portion of the plug 20 communicating with a pilot gas passage 111, 111a formed in the valve body 10 to be finally communicated with a pilot gas nozzle 105 for discharging pilot gas to be ignited by an igniting means 14 secured to the valve body 10.
When the knob 30 is rotated to rotate the plug 20 to match the large opening 211 with the gas inlet port 12, the gas (fuel gas) will be directed through the opening 211, the central hole 21 to respectively direct gas to the nozzles 105, 114 and 115, in which the pilot gas is first ignited at nozzle 105 by the igniting means 14 to start the burning of the large nozzle 115 and the small nozzle 114, both nozzles 115, 114 forming an outer-ring gas burner and an inner-ring gas burner (not shown) for cooking or heating purpose for the gas oven. Two air adjusting means 40 are provided on the two nozzles 115, 114 for adjusting the primary air for helping combustion of the gas.
The rotor plug 20 includes a plug portion having the central longitudinal hole 21 formed therein and a stem 22 secured with the rotating knob 30. A sealing member (not shown) may be provided in the stem to prevent gas leakage from the stem if being made as a hollow stem as shown in the figures.
Such a conventional gas oven may sometimes cause an incomplete combustion of the gas, if for instance the gas oven is operated for burning the gas in a closed room or kitchen, thereby producing carbon monoxide which is poisonous and hazardous to human life and causing coking or accumulation of carbon black on the utensils due to the incomplete combustion of the gas.
The present inventor has found the deflects of a conventional gas oven and invented the present invention having a supply of combustion aid for helping a complete gas combustion of a gas oven.